The Comparative Utility of Structured Lessons, Group and Individually Contingent Events, and Conditioned Reinforcers in Modifying Classroom Behaviors

A major purpose of the study was to assess the relative merits of group versus individually contingent consequences in modifying the classroom behavior of adolescents, Other major purposes were to determine whether student conduct would improve with the implementation of structured lessons and to ascertain whether improvements would occur with the awarding of points as a consequence for appropriate behavior without the use of backup reinforcers. Eight students in an inner-city seventh grade classroom of 32 blacks served as the subjects. They were selected by the teacher as the most disruptive students who were in regular attendance. The eight subjects and the teacher were observed daily for 60 days in math and for 67 days in geography. Observation of students was conducted to determine the effectiveness of experimental conditions, while rating of teacher behavior was carried out to evaluate whether his behavior changed under the different treatments. Treatments were applied successively in math and geography, and, except for the final phase in geography, a session in one class always corresponded to a session in the other class period, The phases were: math--baseline, geography--baseline; math--structured lessons, geography-baseline continued; math--group contingent free time, geography--structured lessons; math--structured lessons, geography--group contingent free time; math--individually contingent free time, geography--structured lessons; math--structured lessons, geography--individually contingent free time; math--points, geography--structured lessons; geography--points. The structured lessons involved the daily specification of rules for classroom conduct and a mimeographed handout of the day\u27s lesson being presented to each child as he entered the class. Subsequently, other consequences (e.g., group contingent free time) were simply added to or subtracted from the structured lessons, Under the individually contingent free time, any student could earn free time privileges (e.g., getting to talk with friends, study other lessons) contingent upon meeting a predetermined criterion of appropriate behavior. During the group procedure free time privileges were dependent upon the combined behavior of the class. The points phases consisted of students earning points for desired behaviors, but the points could no longer be used to purchase free time as had been the case under the individually contingent free time phase. Line graphs were plotted to illustrate the percentages of appropriate behaviors of the subjects for each day of the study. Nonparametric statistics were also used to analyze changes in appropriate behavior as a function of experimental conditions. Tabular presentations and histograms were the primary methods employed in illustrating teacher behaviors. Every treatment condition in math yielded statistically higher levels of appropriate student behavior than the baseline. Similarly, only the structured lessons in geography were not statistically different from baseline. The group and individually contingent consequences produced significantly higher rates of desired behaviors than the other treatments. The group procedure in math, but not in geography, was statistically superior to the individually contingent free time. Overall, the class achieved the highest rates of appropriate behavior during the group contingent free time phases, Individually contingent free time ranked second in the production of positive effects. Points, structured lessons, and baseline yielded successively lower rates of desired responses. Both the structured lessons and points phases resulted in increased percentages of appropriate classroom behaviors, but their power to modify student behaviors enough to establish a semblance of effective.classroom control was not demonstrated, Although the group contingent consequences were found to be the most potent treatment, both group and individually contingent free time proved to be powerful techniques for a beginning teacher to use in improving and sustaining desired student behaviors. From the standpoint of teacher time, the group procedure appeared more efficient since consequences had to be dispensed only once for the entire class as opposed to awarding free time to 32 individual students. Finally, statistical analyses of results across math and geography revealed that treatment effects were highly specific to the setting in which they were applied

Institutional corruption and election fraud: evidence from a field experiment in Afghanistan

We investigate the relationship between political networks, weak institutions, and election fraud during the 2010 parliamentary election in Afghanistan combining: (i) data on political connections between candidates and election officials; (ii) a nationwide controlled evaluation of a novel monitoring technology; and (iii) direct measurements of aggregation fraud. We find considerable evidence of aggregation fraud in favor of connected candidates and that the announcement of a new monitoring technology reduced theft of election materials by about 60 percent and vote counts for connected candidates by about 25 percent. The results have implications for electoral competition and are potentially actionable for policymakers

Calcium and magnesium absorption and retention by growing goats offered diets with different calcium sources

Calcium addition is necessary in order to balance the high phosphorus concentrations that are characteristic of high-concentrate ruminant diets. However, calcium sources differ in their bioavailability. Our objective was to determine apparent calcium and magnesium absorption and retention in goats offered diets containing different sources of calcium. Spanish-Boer goats (n = 18; 19.6 ± 1.88 kg) were stratified by body weight (BW) and sex and randomized to dietary treatments consisting of Purina Antlermax 16 containing either calcium carbonate (CC), Calmin (CM) or Milk Cal (MC). Goats were adapted to a control, corn-based high-concentrate diet on pasture and then moved to individual 1.0 × 1.5-m pens with plastic coated expanded metal floors, and adjusted to their respective diets along with removal of hay from the diet over a 7-d period. Goats were then offered their respective diets at a total of 2% of BW in equal feedings at 8:30 AM and 5:00 PM for an additional 14-d adaption period to diet and facilities followed by a 7-d collection of total urine and feces. Data were analyzed using PROC MIXED of SAS. Calcium and magnesium intake were not different (P ≥ 0.12) among diets. Calcium and magnesium apparent absorption and retention (g/d and % of intake) were greatest (P \u3c 0.05) in goats offered CC and did not differ (P ≥ 0.20) between goats offered the CM and MC diets. Therefore, calcium and magnesium were more available for goats from the diet containing calcium carbonate compared with diets containing Calmin and Milk Cal

Genomes, expression profiles, and diversity of mitochondria of the White-footed Deermouse Peromyscus leucopus, reservoir of Lyme disease and other zoonoses.

The cricetine rodents Peromyscus leucopus and P. maniculatus are key reservoirs for several zoonotic diseases in North America. We determined the complete circular mitochondrial genome sequences of representatives of 3 different stock colonies of P. leucopus, one stock colony of P. maniculatus and two wild populations of P. leucopus. The genomes were syntenic with that of the murids Mus musculus and Rattus norvegicus. Phylogenetic analysis confirmed that these two Peromyscus species are sister taxa in a clade with P. polionotus and also uncovered a distinction between P. leucopus populations in the eastern and the central United States. In one P. leucopus lineage four extended regions of mitochondrial pseudogenes were identified in the nuclear genome. RNA-seq analysis revealed transcription of the entire genome and differences from controls in the expression profiles of mitochondrial genes in the blood, but not in liver or brain, of animals infected with the zoonotic pathogen Borrelia hermsii. PCR and sequencing of the D-loop of the mitochondrion identified 32 different haplotypes among 118 wild P. leucopus at a Connecticut field site. These findings help to further establish P. leucopus as a model organism for studies of emerging infectious diseases, ecology, and in other disciplines

A Second-Generation Janus Scorpionate Ligand: Controlling Coordination Modes in Iron(II) Complexes by Steric Modulation

The second-generation Janus scorpionate ligand [HB(mtdaMe)3−] containing methyl-mercaptothiadiazolyl (mtdaMe) heterocyclic rings and (N,N,N-) and (S,S,S-) binding pockets has been prepared. The effect of methyl substitution versus the unsubstituted first-generation Janus scorpionate [HB(mtda)3]− on the coordination chemistry with alkali metals and on the binding preferences and on the ground spin state of iron(II) complexes has been studied structurally and by 57Fe Mossbauer Spectroscopy

Violence and risk preference: experimental evidence from Afghanistan

We investigate the relationship between violence and economic risk preferences in Afghanistan combining: (i) a two-part experimental procedure identifying risk preferences, violations of Expected Utility, and specific preferences for certainty; (ii) controlled recollection of fear based on established methods from psychology; and (iii) administrative violence data from precisely geocoded military records. We document a specific preference for certainty in violation of Expected Utility. The preference for certainty, which we term a Certainty Premium, is exacerbated by the combination of violent exposure and controlled fearful recollections. The results have implications for risk taking and are potentially actionable for policymakers and marketers

Validation Results: Utah and Western Sierra Variants of the Forest Vegetation Simulator

The Forest Vegetation Simulator (FVS) is the most widely available and used growth and yield model in the US. It is used in both forest management and research and the basic model framework is integrated with post-processors which can be used for many useful analyses (e.g., fire effects, bark beetle susceptibility, etc.). Recent identification of the nomenclature and a basic validation procedure has resulted in a nation-wide effort to objectively test individual FVS variants following a specific protocol (FVS Validation Subcommittee 2009). Despite the huge range of possibilities for model use, and some independent testing of various model components, (e.g., Pokharel and Froese 2009; Vacchiano et al. 2008) and variants (Lacerte et al. 2004) a comprehensive evaluation of the basic model output has yet to be done. In this project, deliverables identified as necessary to inform an appropriate model testing procedure included: (1) data set description; (2) model verification; (3) model validation; and (4) model sensitivity analysis

Exchange biased anomalous Hall effect driven by frustration in a magnetic kagome lattice.

Co[Formula: see text]Sn[Formula: see text]S[Formula: see text] is a ferromagnetic Weyl semimetal that has been the subject of intense scientific interest due to its large anomalous Hall effect. We show that the coupling of this material's topological properties to its magnetic texture leads to a strongly exchange biased anomalous Hall effect. We argue that this is likely caused by the coexistence of ferromagnetism and geometric frustration intrinsic to the kagome network of magnetic ions, giving rise to spin-glass behavior and an exchange bias